Fluid therapy is important during surgery to maintain hemodynamic stability. All fluid losses must be accounted for, including maintenance needs, deficits from fasting or bowel prep, third spacing from tissue trauma, and blood loss. Intraoperative fluids are given as crystalloids like lactated Ringer's or colloids like hetastarch to replace losses based on the type and length of surgery. Goals of fluid management include adequate urine output, normal vital signs, and prevention of organ hypoperfusion.

1. PERIOPERATIVE FLUID
THERAPY
DR.ABDULHADI J. ALAEADEE
CONSULTANT SURGEON
FIBMS M.B.Ch.B

4. Body Water Compartments
• Intracellular water: 2/3 of TBW
• Extracellular water: 1/3 TBW
- Extravascular water: 3/4 of extracellular water
- Intravascular water: 1/4 of extracellular water

5. Fluid and Electrolyte Regulation

8. Preoperative Evaluation
of Fluid Status
• Factors to Assess:
- h/o intake and output
- blood pressure: supine and standing
- heart rate
- skin turgor
- urinary output
- serum electrolytes/osmolarity
- mental status

9. Orthostatic Hypotension
• Systolic blood pressure decrease of greater than 20mmHg
from supine to standing
• Indicates fluid deficit of 6-8% body weight
- Heart rate should increase as a compensatory measure
- If no increase in heart rate, may indicate autonomic dysfunction or
antihypertensive drug therapy

10. Perioperative Fluid Requirements
The following factors must be taken into account:
1- Maintenance fluid requirements
2- NPO and other deficits: NG suction, bowel prep
3- Third space losses
4- Replacement of blood loss
5- Special additional losses: diarrhea

11. 1- Maintenance Fluid Requirements
• Insensible losses such as evaporation of water from
respiratory tract, sweat, feces, urinary excretion. Occurs
continually.
• Adults: approximately 1.5 ml/kg/hr
• “4-2-1 Rule”
- 4 ml/kg/hr for the first 10 kg of body weight
- 2 ml/kg/hr for the second 10 kg body weight
- 1 ml/kg/hr subsequent kg body weight
- Extra fluid for fever, tracheotomy, denuded surfaces

12. 2- NPO and other deficits
• NPO deficit = number of hours NPO x
maintenance fluid requirement.
• Bowel prep may result in up to 1 L fluid loss.
• Measurable fluid losses, e.g. NG suctioning,
vomiting, ostomy output, biliary fistula and tube.

13. 3- Third Space Losses
• Isotonic transfer of ECF from functional body
fluid compartments to non-functional
compartments.
• Depends on location and duration of surgical
procedure, amount of tissue trauma, ambient
temperature, room ventilation.

14. Replacing Third Space Losses
• Superficial surgical trauma: 1-2 ml/kg/hr
• Minimal Surgical Trauma: 3-4 ml/kg/hr
- head and neck, hernia, knee surgery
• Moderate Surgical Trauma: 5-6 ml/kg/hr
- hysterectomy, chest surgery
• Severe surgical trauma: 8-10 ml/kg/hr (or more)
- AAA repair, nehprectomy

15. 4- Blood Loss
• Replace 3 cc of crystalloid solution per cc of
blood loss (crystalloid solutions leave the
intravascular space)
• When using blood products or colloids replace
blood loss volume per volume

16. 5- Other additional losses
• Ongoing fluid losses from other sites:
- gastric drainage
- ostomy output
- diarrhea
• Replace volume per volume with crystalloid
solutions

17. Example
• 62 y/o male, 80 kg, for hemicolectomy
• NPO after 2200, surgery at 0800, received bowel
prep
• 3 hr. procedure, 500 cc blood loss
• What are his estimated intraoperative fluid
requirements?

18. Example (cont.)
• Fluid deficit (NPO): 1.5 ml/kg/hr x 10 hrs = 1200 ml +
1000 ml for bowel prep = 2200 ml total deficit: (Replace
1/2 first hr, 1/4 2nd hr, 1/4 3rd hour).
• Maintenance: 1.5 ml/kg/hr x 3hrs = 360mls
• Third Space Losses: 6 ml/kg/hr x 3 hrs =1440 mls
• Blood Loss: 500ml x 3 = 1500ml
• Total = 2200+360+1440+1500=5500mls

19. Intravenous Fluids:
• Conventional Crystalloids
• Colloids
• Hypertonic Solutions
• Blood/blood products and blood substitutes

20. Crystalloids
• Combination of water and electrolytes
- Balanced salt solution: electrolyte composition and
osmolality similar to plasma; example: lactated
Ringer’s, Plasmlyte, Normosol.
- Hypotonic salt solution: electrolyte composition lower
than that of plasma; example: D5W.
- Hypertonic salt solution: 2.7% NaCl.

21. Colloids
• Fluids containing molecules sufficiently large
enough to prevent transfer across capillary
membranes.
• Solutions stay in the space into which they are
infused.
• Examples: hetastarch (Hespan), albumin, dextran.

22. Hypertonic Solutions
• Fluids containing sodium concentrations greater than
normal saline.
• Available in 1.8%, 2.7%, 3%, 5%, 7.5%, 10% solutions.
• Hyperosmolarity creates a gradient that draws water out
of cells; therefore, cellular dehydration is a potential
problem.

23. Composition
Fluid Osmo-
lality
Na Cl K
D5W 253 0 0 0
0.9NS 308 154 154 0
LR 273 130 109 4.0
Plasma-lyte 294 140 98 5.0
Hespan 310 154 154 0
5% Albumin 308 145 145 0
3%Saline 1027 513 513 0

24. Clinical Evaluation of Fluid
Replacement
1. Urine Output: at least 1.0 ml/kg/hr
2. Vital Signs: BP and HR normal (How is the patient doing?)
3. Physical Assessment: Skin and mucous membranes no dry;
no thirst in an awake patient
4. Invasive monitoring; CVP or PCWP may be used as a
guide
5. Laboratory tests: periodic monitoring of hemoglobin and
hematocrit

25. Summary
• Fluid therapy is critically important during the
perioperative period.
• The most important goal is to maintain
hemodynamic stability and protect vital organs
from hypoperfusion (heart, liver, brain, kidneys).
• All sources of fluid losses must be accounted for.
• Good fluid management goes a long way toward
preventing problems.

26. Packed Red Blood Cells
• 1 unit = 250 ml. Hct. = 70-80%.
• 1 unit pRBC’s raises Hgb 1 gm/dL.
• Mixed with saline: LR has Calcium which may
cause clotting if mixed with pRBC’s.

27. Platelet Concentrate
• Treatment of thrombocytopenia
• Intraoperatively used if platlet count drops below 50,000
cells-mm3 (lab analysis).
• 1 unit of platelets increases platelet count 5000-10000
cells-mm3.
• Risks:
- Sensitization due to HLA on platelets
- Viral transmission

28. Fresh Frozen Plasma
• Plasma from whole blood frozen within 6 hours of
collection.
- Contains coagulation factors except platelets
- Used for treatment of isolated factor deficiences, reversal of
Coumadin effect, TTP, etc.
- Used when PT and PTT are >1.5 normal
• Risks:
- Viral transmission
- Allergy

29. The daily requirements of water and electrolytes in an adult
are: .
Water 3Sml/kg. .
Sodium lmmol/kg. .
 Potassium l mmol/kg.
 *The usual daily postoperative fluids for uncomplicated
surgery in an adult: .
Three liters of fluids=6 bottles.
Add200ml per day for each 1'c rise in temperature.
. 500 ml saline (0.9% sodium chloride) provides the daily
requirements of sodium and chloride. .

30. . The remaining volume requirement (2.5L=5 bottles) is
given as 5%dextrose(glucose). .
Potassium supplements are given after 48 hours.

31. THANKS